For a long time, a feature size of a metal-oxide-semiconductor field-effect transistor (MOSFET) is scaled down according to Moore's law, and a working speed of the MOSFET is faster and faster. However, physical and technical limits of Si materials have been reached. Therefore, in order to improve a performance of the MOSFET, various methods have been proposed, and consequently a More-than-Moore era has come. Among them, an effective technology is a high-mobility channel engineering based on heterogeneous materials, particularly, high-carrier-mobility materials such as Si—Ge materials and III-V compound materials.
Because lattice constant of Si is different from Ge and Group III-V compound semiconductor materials, there is a high density dislocation in Ge or III-V compound film heterogeneously integrated on Si substrate, and consequently serious scattering and leakage may be caused, thus influencing a performance of a device.